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Bob McDavitt's ideas for sailing weather around the South pacific

26 June 2016

Bob Blog 26 June 2016

WEATHERGRAM
YOTREPS
Issued 26 June 2016
Bob McDavitt's ideas for sailing around the South Pacific.
Disclaimer: Weather is a mix of pattern and chaos; these ideas are from the
patterned world.

Sea Mercy is making good progress in Fiji. Marie Dufour on cat DOMINO has
written a blog about conditions and needs in the villages they have visited,
read this at dominocatamaran.blogspot.co.nz/ and read the adventures of SV PERRY
at www.svperry.com/2016/06/the-lau-group-fiji.html#more

In the past week (the week after the winter solstice) there have been some
stormy weather around the planet. The monsoon arrived as a burst of
thunderstorms in India, with 93 people killed by lightning strikes in 2 days.
Bihar, an eastern state was hardest hit, with 59 confirmed deaths. mainly
farmers planting rice.
The Monsoon advance may be seen at www.imd.gov.in/pages/monsoon_main.php
Heavy rain has also visited South China, triggering a fatal tornado /hail storm
which claimed 98 lives in east China's Jiangsu Province. And heavy flooding has
brought widespread damage to West Virginia in the United States of North
America, killing at least 26 people.

Tropics are still having a cyclone drought.
Some tropical lows near and north of the Philippines, otherwise quiet, or so it
seems.
Last fortnight of weekly rain profiles ( from
trmm.gsfc.nasa.gov/trmm_rain/Events/big_global_accumlation.gif) shows that the
heaviest rain is now shifting east across Vietnam/South China and towards
Philippines. That's normal. The Tasman Sea area has switched from dry to wet.

WEATHER ZONES
SPCZ=South Pacific Convergence zone.
SPCZ is expected to remain draped from PNG across to the Tuvalu/Tokelau area,
then to Northern Cooks. The GFS model is picking that a trough may develop on
the SPCZ in the Coral Sea around 4/5 July and then move onto New
Caledonia/Vanuatu around 6/7 July, but this is NOT being forecast by the ECMWF
model at this stage, so can be treated as a 50% probability.

STR= Sub-tropical Ridge
STR is along 25 to 30S in Tasman Sea but more like 35 to 40S east of NZ.
The HIGH that is east of NZ near 40S and south of French Polynesia is expected
to travel slowly east along around 40S this week going towards South America.
The next HIGH over eastern Australia on Tue to Thurs is expected to fade as it
crosses the Tasman on Friday and NZ on Saturday. It will probably fade so much
that it is not going to offer a large enough gap-between-lows for yachts seeking
to depart from NZ for the tropics.

Voyage Outlooks:
Tahiti to the west
Satellite imagery shows the convergence zone over Tahiti tonight. This is
expected to weaken and shift to the north during tomorrow, bringing strong SE
winds and dry conditions to the Borabora/to Papeete area on local Monday. From
late local Monday these winds should moderate, and then there is likely to be a
dry period with light to moderate SE/E winds over the Tahiti area for the next
week or mare. That's a change from the recent wet windy weather in the area.
Since the SPCZ is expected to remain north of 15s, it appears that a voyage to
the west should travel along the drier and more settled latitudes near 17 to
19S.
Weather may not remain settled all the way from Tahiti to Tonga, as a weak
trough from the SW may travel across Tonga around 1-3 July, followed by SW
swells. So it may be desirable to stop at an Island such as Palmerston Island
or Niue /Beveridge reef along the way.

Between NZ and the tropics
MAYBE NOT this week (again), may as well stay put (again). A LOW is crossing NZ
on Monday, and then a brief ridge on Tuesday. Too brief for getting away, as
the next LOW is expected on Wed/Thu/Fri. Then another brief ridge on Saturday
followed by a LOW on Mon/Tue 4/5 July, and a front on Wed 6 July. Maybe OK to
sail north on Thu 7 July, too far away to tell.

Between Australia and New Caledonia/Fiji
OK, wait for sea to settle after Monday's Tasman Low, maybe Wed or Thursday.
Then should be Ok to sail to New Caledonia/Fiji.
>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>
See my yotpak at boatbooks.co.nz/weather.html for terms used.
See my website www.metbob.com for information on tailor-made voyage forecasts
- Feedback to bob@metbob.com.
Tell anyone you like that to subscribe they should email me.
Weathergram text only (and translator) is at weathergram.blogspot.co.nz.
Weathergram with graphics is at metbob.wordpress.com,
click FOLLOW at bottom right to subscribe.
To unsubscribe send a reply email saying LEAVE.

19 June 2016

Bob Blog 19 June

WEATHERGRAM
YOTREPS
Issued 19 June 2016

Bob McDavitt's ideas for sailing around the South Pacific.
Disclaimer: Weather is a mix of pattern and chaos; these ideas are from the
patterned world.

The winter solstice is upon us. The sun "stands still" at 1034UTC on 21 June.
This is when its declination (as seen from earth) is most south and it "stands"
before turning north. It's the longest night/shortest day and one of the four
turning pints of the year. Yet meteorologicaly it has very little meaning and is
really the START of the three coldest months in the southern hemisphere. The
coldest time of the year is usually 6 weeks AFTER the solstice: hence the saying
"when the days start getting longer, the dawns gets colder".
Enough misery, now for some GOOD news.

El Nino continues to fade
The heat stored in the top layers of the sea over the eastern equatorial Pacific
has been steadily dropping and is now almost in the NEUTRAL range. The monthly
NINO3.4 graph at www.farmonlineweather.com.au allows us to compare the recent El
Nino with the previous "big one" of 1997/98. Our recent El Nino has lasted
longer and was slightly stronger. Curious climatologists are thinking this is
part of a trend, but it is difficult to tell.
The SOI index has also been in the NEUTRAL zone for the past two weeks.


Tropics are still quiet- maybe a drought of cyclone?
India's monsoon is making progress, but still around 10 days behind schedule.
Last fortnight of weekly rain profiles from
trmm.gsfc.nasa.gov/trmm_rain/Events/big_global_accumlation.gif shows that the
heaviest rain is now shifting from Myanmar/Burma to Vietnam/South China. That's
normal.

WEATHER ZONES
SPCZ=South Pacific Convergence zone.
SPCZ is expected to remain draped from PNG across to the Tuvalu/Tokelau area,
then Northern Cooks to Tuamotu Islands. The zone currently has a break in it
over Suwarrow, but that is not expected to last long. See windyty.com an select
rain accumulation next 10days.

STR= Sub-tropical Ridge
STR is along 25 to 30S in Tasman Sea but more like 35 to 40S east of NZ.
The HIGH that is east of NZ tonight is expected to travel slowly east along
around 40S this week then go NE next week towards 30S. There is expected to be a
squash zone between this High and the low on its northern side, but this is only
expected to affect sailors in-between NZ and Tahiti.

Voyage Outlooks:
Tahiti to the west
A trough is approaching Tahiti with NE winds preceding it, so best wait for it
to come and go and depart around wed/Thu 22/23 June local. Such a voyage should
have OK winds, but may encounter some squalls around 27 June local. Too early to
tell for sure, for sure.

Between NZ and the tropics
NOPE. NOT this week, may as well stay put. The NE winds that precede the next
trough are expected to spread onto Northland from Monday, then the trough on
Wednesday, and another on Saturday, this is OK for those going east to Tahiti,
but NOT for anyone going to Tonga/Fiji/New Caledonia/Australia. May as well do
something else.

Between Australia and New Caledonia
YEP. OK, wait for sea to settle after Sunday's night trough, then should be Ok
to sail to New Caledonia. But make it quick, as the next rough is likely over
Queensland by Friday
>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>
See my yotpak at boatbooks.co.nz/weather.html for terms used.
See my website http://www.metbob.com for information on tailor-made voyage
forecasts- Feedback to bob@metbob.com. Tell anyone you like that to subscribe
they should email me.
Weathergram text only (and translator) is at weathergram.blogspot.co.nz.
Weathergram with graphics is at metbob.wordpress.com, click FOLLOW at bottom
right to subscribe.
To unsubscribe from WordPress: click the "unsubscribe" link on the bottom of the
email. Or, if email wasn't from WordPress then send a reply email saying LEAVE.

12 June 2016

Bob Blog 12 June 2016

WEATHERGRAM
YOTREPS
Issued 12 June 2016

Bob McDavitt's ideas for sailing around the South Pacific.
Disclaimer: Weather is a mix of pattern and chaos; these ideas are from the
patterned world.

Just a quick blog this evening, it's been a long day here.
Tropics are quiet at present. India's monsoon seems to be advancing, but is
around 5 to 10 days "late".
The advance of the 2016 Monsoon may be seen at
www.imd.gov.in/pages/monsoon_main.php
Last week's rain has been heaviest in Myanmar/Burma, as seen at
trmm.gsfc.nasa.gov/trmm_rain/Events/big_global_accumlation.gif .

WEATHER ZONES
SPCZ=South Pacific Convergence zone.
SPCZ is expected to remain draped from PNG across to the Tuvalu/Tokelau area,
with a touch over Northern Cooks. The cloud band that is now moving off to east
of Tonga is associated with a weak trough still south of Fiji. This is expected
to travel east (upper westerly winds) like an "easterly wave" and reach Southern
Cooks by end of this week.

STR= Sub-tropical Ridge
STR is near 35. The HIGH over southeast Australia this weekend looks intense
with central pressure over 1038, but is expected to fade as it tries to move
into Tasman Sea, and end of the week may be just over1028 over northern NZ. A
squash zone is likely over southern Coral Sea between this High and that trough
southeast of Fiji.

Voyage Outlooks:
Travelling to Marquesas:
Winds near Isla Isabela are expected to be light southerly this week, possibly
reaching 10 knots on local Thu/Fri. May as well get best from the current by
going to 5S then west to 127W and then direct. And around Marquesas Islands
expect moderate east to NE winds.

Tahiti to the west
There is currently a squash zone over Tahiti area, and this should ease local
Sunday/Monday so that departure may be Ok local Tuesday (giving seas a day to
settle down). Since the SPCZ is active over its northern region, this suggests a
voyage to Palmerston/Niue may be squall free, and a voyage to Suwarrow may
encounter squalls.

Between NZ and the tropics
Conditions are good to go from Monday morning once a passing front has brought a
southerly change to Northland area. The HIGH that is following this front is
expected to weaken slowly as it travels across the Tasman Sea and should sustain
a SSE/Se 20 knot flow to Vanuatu/Fiji. The path to Tonga may need to deviate
around a trough in order to avoid a calm area. The path to Noumea may encounter
a squash zone associated with the HIGH.

The trough that follows that HIGH is expected to arrive in Tasman Sea around
Sat/Sun 18/19 June. This may trigger a Low to deepen east of Brisbane early next
week, and LOW should travel southeast towards NZ. Associated E/NE winds and
trough may reach New Caledonia Sun19/Mon 20 June and weaken the winds over
Vanuatu. This complicated voyages in those directions.

Between Australia and New Caledonia
Squash Zone between High and New Caledonia from Monday to Thursday.
Then a trough is likely offshore Brisbane on Friday to Sunday.
Better to go next week.

>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>
See my yotpak at boatbooks.co.nz/weather.html for terms used.
See my website http://www.metbob.com for information on tailor-made voyage
forecasts-
Feedback to bob@metbob.com. Tell anyone you like that to subscribe they should
email me.
Weathergram text only (and translator) is at weathergram.blogspot.co.nz.
Weathergram with graphics is at metbob.wordpress.com, click FOLLOW at bottom
right to subscribe.
To unsubscribe send a reply email saying LEAVE.

05 June 2016

Bob Gram 5 June 2016. Lau Aid and a Big Fat High.

WEATHERGRAM
YOTREPS
Issued 05 June
Bob McDavitt's ideas for sailing around the South Pacific.
Disclaimer: Weather is a mix of pattern and chaos; these ideas are from the
patterned world.

LAU AID:
Here's a detailed report from the 4M's, crew of AMELIE IV, a Sea Mercy Aid
vessel that arrived a week ago in Fiji:
>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>
Well it's been a bit over a week in the Lau Group and looking back it seems like
longer! We've assisted or completed 'Needs Assessments' for 5 villages on 3
different islands, and visited 3 additional villages that other Sea Mercy boats
had previously completed assessments on. The level of impact was surprisingly
varied across a relatively small distance (40 nm) and with that the
corresponding needs were quite diverse. We've now met up with the other 8 boats
in the Sea Mercy DR2A fleet to spend some time comparing notes between teams to
prioritize our efforts and our requests for supply materials. As re-establishing
reliable water sources is either urgent or will be urgent in a lot of the
villages, as the dry season progresses, that's where a lot of our efforts will
be first focused, but there's clearly a lot more needed here. It was humbling to
realize that the estimated $ Sea Mercy has already raised for this area really
only starts to cover what we've identified for re building catchment and lost
storage capabilities, let alone the myriad of other health, food, education and
sanitation needs identified. The good news is that the reports we've made are
also being used by other aid organizations that have focuses on these areas so
part of our role is to be eyes and ears for them as we've got 'boots on the
ground' here and they don't currently.

In the meantime though, there will be lots to keep us busy. A mega-yacht was
here earlier this week on the other side of the island to off load water to a
few villages that were critically short so a few of the yachts helped coordinate
and make the most of the time the mega-yacht was available. A few of us then
spent some time over the last few days helping a couple of the villages clear
away deadfall with chainsaws we brought from NZ, while others from the yachts
assisted with their community gardens and setting up composting facilities.

Next week there are strong winds forecast, so we'll stay based out of here and
focus on the Vanua Balavu villages. I'm going to the village of Mavana with some
fiberglass repair kits donated by Burnsco in NZ, to try to get two of the
village longboats back in the water, while another group will come to help
repair the community hall roof that they've already got materials for. Some
other groups will continue working with the villages on their gardens for both
food and cash crops as a new income stream to help offset what they've lost from
copra.

The week after, once the winds abate a bit, we'll likely be trying to get back
out to some of the other islands again for some small projects and possibly
water projects with a portable RO unit. It is apparent though that the all plans
are 'written in sand at low tide', and will need to be re-evaluated as needs
change, resources become available and more information becomes apparent. So,
we'll see what develops...........
>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>
And a reminder that ordinary yachts now visiting Fiji can help Sea Mercy or
Oxfam with aid missions. Some cruisers may not interested in carrying materials,
but may want to employ their own skills. Many do not realise that Sea Mercy
offers those types of opportunities. Some want to know how or where agencies are
prioritising their aid, so here is some info about Oxfam as well. If you are in
Fiji and have a few days at a loose-end, I recommend you email one of the links
below to add extra memories to your adventure:
>>>>>>>>>>>>>>>>>>>>>
In Fiji, Oxfam is supporting TC Winston affected people in Fiji with Water
sanitation and hygiene promotion work in most affected provinces:
Northern - Bua and Cakadrove
Western - Ra
Central - Naitisiri and Tailevu
In Vanuatu, Oxfam is supporting drought affected people, and continuing
reconstruction from TC Pam, mostly in Shefa province.
I am sure sailors with electrical/solar, plumbing, mechanical and construction
skills would be most welcome in these regions.
Sea Mercy is dealing with the distribution of educational, health and
construction materials in Fiji. They have warehouses where cruisers can pick up
materials to take to outer islands. Please contact:
nigel@seamercy.org
People are welcome to email me if they have questions about engaging in
humanitarian relief efforts. Thank you! -- Dina Aloi, SV Good as Gold,
www.svgoodasgold.ca
>>>>>>>>>>>>>>>>>>>>>>>>>>>>>
The Tropics
Tropical System Bonnie, the first of the year to threaten the United States, has
been lingering offshore all week and is still a remnant depression in the
Atlantic.
A tropical depression is expected to form in the eastern North pacific this week
near 11S 120W, but should fade as it travels west.
The Indian Monsoon stalled last week and is now about a week behind normal. The
Consequential heatwave is purported to be the warmest in India for centuries.
but so far is not as deadly as last year (in 2015, over 2500 deaths were
attributed to the pre-monsoon heat wave).
The Heat wave (for eastern areas) may be seen at
bhuvan-noeda.nrsc.gov.in/governance/heatwave.
The Advance of the monsoon may be seen at www.imd.gov.in/pages/monsoon_main.php
Rain maps from trmm.gsfc.nasa.gov/trmm_rain/Events/big_global_accumlation.gif
for the past fortnight show a weakening in the intensity and spread of the South
Pacific Convergence zone, and the extreme rainfall along Australia's east coast.


WEATHER ZONES
SPCZ=South Pacific Convergence zone.
SPCZ is expected to remain draped from PNG across to the Tuvalu/Tokelau area,
with a touch over northern Cooks. A passing trough is tonight over New Caledonia
and is expected to cross the Vanuatu area on Monday local, Fiji on Thursday
local and then weaken between Fiji and Tonga by Saturday. If this trough is in
the way of your plans think about avoiding it, as it is likely to contain
squalls. One yacht got hit at 18S 154W last night with 40 gusting 50 knot winds.

STR= Sub-tropical Ridge
The HIGH over NZ this weekend is a BIG FAT HIGH with central pressure near
1040hPa as seen in today's analysis.
An analysis comes from the real word (100% trustworthy), and all prognosis maps
are ideas from isobar land and as such not be 100% trusted.
When an HIGH becomes as intense as this, extra isobars have to be added to the
weather map. Isobars remain well-spaced near the centre of the HIGH , and so
these extra isobars cause all the isobars between 1012 and 1024 to squeeze
together forming what I call a SQUASH ZONE, As you can see form the above map
this intensifies the weather systems around the periphery of the HIGH. The
trough along the eastern seaboard of Australia tonight gets extra help in
deepening from the warm seas of the east Australian current, and you can see how
the gales are building huge waves and pushing them onto Tasmania.

Voyage Outlooks:
Panama to Galapagos:
Light to moderate southerly winds around Panama this week, so not a good week to
depart. Also the ITCZ seems to be active and squally at times between 8N and 5N,
so another week when it's better to stay put. There may be a change to northerly
winds near Panama after 19 June.

Travelling to Marquesas:
Winds near Isla Isabela are expected to be light southerly this week, possibly
reaching 10 knots on local Fri/Sat.
May as well get best from the current by going to 4S 100W then west to 5S 130W
and then direct.
And around Marquesas Islands expect moderate east to NE winds.

Tahiti to the west
A passing trough (with showers) is likely to bring Tahiti area NW winds until
local Monday, so wait until Tuesday.
BFH to the south travelling east along 33S from local wed to Friday may produce
a squash zone of enhanced SE winds along the route at 18S, but this can be
avoided by going to 17S.

Between NZ and the tropics
After the BFH there is an intense, but weakening, trough now expected to arrive
around Wednesday, but it may take until Friday before the seas settle over
Northland after that trough.

Between Australia and New Caledonia
The intense trough has already cleared the Queensland are, but seas may still be
rough on Monday.
Tuesday looks to be the best day this week, for after that there are more SE
winds to negotiate.
>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>
See my yotpak at boatbooks.co.nz/weather.html for terms used.
See my website www.metbob.com for information on tailor-made voyage forecasts
- Feedback to bob@metbob.com. Tell anyone you like that to subscribe they should
email me.
Weathergram text only (and translator) is at weathergram.blogspot.co.nz.
Weathergram with graphics is at metbob.wordpress.com, click FOLLOW at bottom
right to subscribe.
To unsubscribe send a reply email saying LEAVE.

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